samples/platform_channels/lib/src/event_channel_demo.dart

62 lines
2.1 KiB

// Copyright 2020 The Flutter team. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:platform_channels/src/accelerometer_event_channel.dart';
/// Demonstrates how to use [EventChannel] to listen continuous values
/// of Accelerometer Sensor from platform.
///
/// The widget uses a [StreamBuilder] to rebuild it's descendant whenever it
/// listens a new value from the [Accelerometer.readings] stream. It has three
/// [Text] widgets to display the value of [AccelerometerReadings.x],
/// [AccelerometerReadings.y], and [AccelerometerReadings.z] respectively.
class EventChannelDemo extends StatelessWidget {
const EventChannelDemo({super.key});
@override
Widget build(BuildContext context) {
final textStyle = Theme.of(context).textTheme.headlineSmall;
return Scaffold(
appBar: AppBar(
title: const Text('EventChannel Demo'),
),
body: Center(
child: StreamBuilder<AccelerometerReadings>(
stream: Accelerometer.readings,
builder: (context, snapshot) {
if (snapshot.hasError) {
return Text((snapshot.error as PlatformException).message!);
} else if (snapshot.hasData) {
return Column(
mainAxisAlignment: MainAxisAlignment.center,
children: [
Text(
'x axis: ${snapshot.data!.x.toStringAsFixed(3)}',
style: textStyle,
),
Text(
'y axis: ${snapshot.data!.y.toStringAsFixed(3)}',
style: textStyle,
),
Text(
'z axis: ${snapshot.data!.z.toStringAsFixed(3)}',
style: textStyle,
)
],
);
}
return Text(
'No Data Available',
style: textStyle,
);
},
),
),
);
}
}